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Finding the Fourth Proportional to 509.68, 765.08 and 419.28

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Solution

The fourth proportional to 509.68, 765.08 and 419.28 is: 629.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    509.68 : 765.08 = 419.28 : x
  2. Step 2: Convert to fraction form
    509.68/765.08 = 419.28/x
  3. Step 3: Cross multiply
    509.68x = 765.08 × 419.28
  4. Step 4: Simplify right side
    509.68x = 320,782.74
  5. Step 5: Solve for x
    x = 320,782.74/509.68
  6. Step 6: Final answer
    x = 629.38

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.